A variety of inflatable sport balls, such as soccer balls, conventionally exhibit a layered structure that includes a casing, a restriction structure, and a bladder. The casing forms an exterior portion of the sport ball and is generally formed from a plurality of durable and wear-resistant panels joined together along abutting edges (e.g., with stitching or adhesives). Although panel configurations may vary significantly, the casing of a traditional soccer ball includes thirty-two panels, twelve of which have a pentagonal shape and twenty of which have a hexagonal shape.
The restriction structure forms a middle portion of the sport ball and is positioned between the casing and the bladder. Among other purposes, the restriction structure may provide a softened feel to the sport ball, impart energy return, and restrict expansion of the bladder. In some configurations, the restriction structure or portions of the restriction structure may be bonded, joined, or otherwise incorporated into the casing as a backing material.
The bladder, which has an inflatable configuration, is located within the restriction structure to provide an interior portion of the sport ball. In order to facilitate inflation (i.e., with pressurized air), the bladder generally includes a valved opening that extends through each of the restriction structure and casing, thereby being accessible from an exterior of the sport ball.